<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

<script type="text/javascript">
    var a=parseInt(prompt("请输入一个数"))
    var b=parseInt(prompt("请再输入一个数"))
    var c=a>b?a:b;
    alert("最大值为："+c)
</script>
</body>
</html>